The present invention relates to a power-assisted device or apparatus for raising and lowering a seat and of the general type disclosed in U.S. Pat. No. 5,561,872 issued to applicant. Such apparatus is particularly useful for raising and lowering a toilet seat having a center opening to assist a handicapped person. For such assistance, it is desirable for the apparatus to move the seat between a horizontal lower seating position and a downwardly inclined elevated or upper position projecting substantially forwardly of the lower position so that it is convenient and natural for the person to move to and from a standing position. It is also desirable to simplify the apparatus to minimize the weight and construction cost of the apparatus while also enabling the apparatus to raise and lower a person having substantial weight, for example, over 250 lbs. Relatively complex different forms of power-assisted toilet seat lift apparatus are disclosed in U.S. Pat. Nos. 6,154,896 and 6,161,229, both of which cite applicant""s ""872 patent.
The present invention is directed to an improved apparatus for raising and lowering a seat between a horizontal lower seating position and a downwardly inclined elevated or upper position projecting forwardly of the lower position for assisting a handicapped person, and which is ideally suited for mounting on a toilet for raising and lowering a toilet seat. The apparatus of the invention is simple and economical in construction and is capable of raising and lowering a person having substantial weight. In addition, the apparatus of the invention may be quickly attached to a toilet base after removing the conventional toilet seat and cover, and is compact so that it does not require additional space beyond either side of the toilet water tank.
In accordance with a preferred embodiment of the invention, a lifting apparatus includes an upper support member or frame and a lower support member or frame having corresponding front portions pivotally connected. A seat, such as an annular toilet seat, overlies the frames and has a rear portion pivotally connected to a rear portion of the upper support member or frame. A pair of scissor linkages are connected to corresponding opposite side portions of the frames and have forwardly projecting arms which support rollers engaging the bottom surface of the seat. A reversible motor driven screw jack unit is supported on either side of the frames by a U-shaped support bracket and has a linear movable actuating rod connected to one side portion of the upper frame for tilting or pivoting the upper frame between a horizontal position adjacent the lower frame and an elevated inclined position while the scissor linkages automatically move the seat between a horizontal seating position and an inclined elevated position projecting forwardly of the frames. A U-shaped handle member is mounted on the front portion of the lower frame and has upper handle grips either of which supports a remote control switch for operating the motor driven screw jack unit.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.